The process of filling cans in bulk usually involves filling the can prior to putting the top onto the can. The process of sealing the top onto the can, called seaming, is carried out by “seamers”.
Seamers come in two broad categories: large, extremely bulky, extremely expensive seamers used in very high volume operations such as large brand beverages, and small, quite slow seamers which are used by micro-breweries and the like.
The typical micro-brewery not only has no use for the speed capacity of the large type of seamer, it also has no space: large seamers are huge devices weighing several tons and taking up significantly more space than a micro-brewery can afford to spare.
On the other hand, the “one at a time” seamers used by micro-breweries will carry cans full of beverage to a station at which the can stops while a lid is seamed onto it individually, before jerking the line of cans back into motion and advancing another single can. Obviously this “start-stop” motion on the part of the cans is not only conducive to out-gassing and sloshing but in addition slows down production dramatically. This is one competitive disadvantage suffered by small craft breweries in comparison to large industrial breweries. Speeding up the seaming of micro-brews would increase production speed and thus lower production costs.
One more interesting disadvantage of this process is that since most micro-brewery can fillers work on several cans at once, for example, on four cans at once, four cans in a row are filled at the same moment, but then they are seamed one at a time, meaning that carbonization (CO2, N2 or other pressurizing agents in beer, soda pop or other beverages) will have unequal times to escape from the open topped cans. The first can in any group of four will be seamed shut first, leaving more of the gas in solution in the beer. The second can will sit a bit longer, and outgas a bit more, before being sealed. The third can will sit a little bit longer yet, and the fourth can will sit for even longer. This means that the “stiffness” (related to the degree of dissolved gases) of each can will be different from that of the cans on either side. In the case of liquid charge dosing, where closely metered quantities of liquefied gas, such as nitrogen, are applied to the surface of the filled liquid prior to lid application, existing seaming methods and devices provide undesirable fluctuation in the amount of time between the steps of applying the dose of liquid, applying the lid, and seaming the lid. This inconsistent timing leads to unacceptable fluctuation in the final pressure within the sealed cans, due to the aforementioned escaping charge prior to seaming. This effect is especially detrimental when canning “still” beverages, or when utilizing internal pressurizing reservoirs, known as “widgets”, which are charged through the liquid nitrogen dosing process.
The large rotary fillers are the most common type found in patent literature. These have star wheels, helical feed screws, and other large structures. In general none of them disclose the concept of lifting the can to the seaming rollers/heads while leaving it in contact, even engaged between the threads of, a continuous motion worm drive.
Turning to the prior art individually, we see a few items of interest.
For example, U.S. Pat. No. 2,563,496 is typical of the prior art: an elaborate and synchronized mechanical filler and seamer unit combined, which puts the lid onto the can prior to changing the direction of travel of the can (in an effort to reduce spillage). It is obviously quite expensive to produce.
U.S. Pat. No. 4,513,487 is for mufflers (vehicle exhaust mufflers) and is thus not relevant art. It operates on two ends of a muffler, not one, and seems to be hand loaded and thus also irrelevant to even small volume production such as microbrewing.
U.S. Pat. No. 6,910,413 uses timing screws to create specified dwell times at different stations of a can decorator. However, the bottles being decorated are carried in individual carriages and the carriages are connected to a worm drive which is not dimensioned and configured for a individual bottle/can. By and large, the apparatus is concerned with controlling the orientation of the bottles.
US Patent Publication No. 20130108399 is most relevant to the context of usage of the present invention, being also designed for smaller beverage manufacturers. This design however is very structurally different, using rotary air actuators and the like.
It would be preferable to provide a can seamer offering a more reliable device and a more reliable seam, as well as the potential for a higher speed of production than devices like the 20130108399 device, in a format suitable for small brewers.
It would further be preferable to provide a can seamer offering a straight through or at least linear can path, usable in-line with the production facility's can path.
It would also be preferable to provide a can seamer offering single device independent mobility, so that it can be easily integrated into existing small brewer production lines.
It would yet further be preferable to provide a continuous motion drive so that cans need not be seamed at irregular time intervals but more importantly so that production speed is increased, without the stop-start motion associated with prior art craft beer seamers